Oh, no! Sunita Williams and Barry "Butch" Wilmore are stranded (according to headlines) or not stranded (according to NASA) aboard ISS! What'll they do?
Ride the Boeing Starliner back down, once the engineers are happy; or hitch a spare pair of seats on a SpaceX Dragon capsule, if the engineers get a lot less happy than they are now. They're not stranded. If the price was right, the Russians would probably taxi them home, and gloat about it all the way.
The worst problem for the pair right now is ensuring a sufficient supply of underwear (etc.). There's no laundromat on ISS; they can't even take dirty clothes outside and let the vacuum sterilize them: the resultant particulate matter would stay in orbit and after a few years, ISS and all the scientific instruments it carries would be orbiting in a thin cloud of schmutz. Astronauts, cosmonauts, tourists and whoever else on ISS bring up a suitcase of employer-issued attire, stuff their dirty laundry into the trash, and it gets packed into a disposable cargo vehicle (From Russia, ESA or JAXA, though the latter two may not be flying at present) and burns up on reentry, raining schmutz-laden ashes down on the oceans and great cities of the world.
The biggest risk they're facing is a shortage of skivvies. NASA has done detailed studies on just how long you can wear the same set of clothes (ickily long), and resupply flights arrive at regular intervals, so not to worry.
But what about those thrusters? The delay seems to stem from some wonky thrusters in the Starliner's Service Module, and the issue there is, that part is not coming home. It gets discarded along the way and burns up, just like a bag of space laundry. If there's any chance to figure out what went wrong, it's got to be before the spacecraft heads home.
And why is there a problem? Can't NASA just pull out their engineering samples here on Earth and start fooling with them? Um, about that.... Even when NASA was building their own spacecraft, they weren't building their own spacecraft. Mostly they were managing the design process, subcontracting construction to a whole flock of companies (Chrysler made big chunks of Saturn V that took us to the Moon!) and managing (and occasionally performing) system integration. It was all done on cost-plus contracts: do the job, whatever it takes, and send Uncle Sam the bill. For the commercial crew system that has produced SpaceX's Dragon and Boeing's Starliner,* NASA has stepped back from micromanaging and final assembly; they described the mission and put it up for bid -- at a fixed price.
SpaceX got in early, using the prototype Dragon capsule and Falcon boosters for the unscrewed resupply contracts and learning as they went. Boeing -- who had absorbed a lot of other aerospace companies and had immense institutional experience building spacecraft -- went straight into building manned vehicles. And, as they had always done, they subcontracted a lot of it. Including the thrusters; those were made by Aerojet Rocketdyne (Owned by L3Harris, itself a child of defense contractor Litton Industries and Harris Intertype, who once made printing presses, broadcast equipment and military communications gear). This was bigtime commercial spaceship stuff, and Boeing asked for -- and got -- a fixed-price contract from their subcontractors.
Space is hard. Rockets break, and they break in many new and unusual ways. Make a change to an existing system, and it may surprise you; design a new system from the ground up and it will surprise you. If the engineers are very talented and very experienced, they can anticipate many of the ways things will fail, but not all of the ways. No one can. SpaceX uses a "move fast and break things" approach, and it works -- but they suffer occasional dramatic failures and have, so far, been very good at knowing how much risk is acceptable for any given flight. NASA, in the wake of the Apollo "plugs-out" ground test tragedy, was obsessed with hand-tightening every bolt, having all the contractors follow every step of every part of the work and materials in extreme detail, and it resulted in successful Lunar missions -- at very great cost. Boeing threw their efforts into engineering and ground-testing -- and in writing careful specifications for the subcontracted subsystems. When things break, it's a matter for figuring out where, why and how -- and if the failure was due to improper assembly, improper design, or flawed specifications. Money is riding on the answer -- money and whose pocket it comes out of. This is not just rocket-geekery; it's attorneys and accountants and managers; it's people's best educated guess on how much it's going to cost to make each widget and how much the prime contractor will pay for it. Get those numbers wrong and you can eat up a year's profit; get them too wrong, and people die.
Starliner's woes do not appear to be at the "people die" point. They have, however, been teetering on the brink of "goodby, profits" for both already-ailing Boeing and some of their subcontractors, and that spaceship its going to to stay up there, docked with ISS, until they have sorted out every valve, bolt, screw, engineering specification, contractual clause and the wounded feelings of the second vice-president in change of making rocketships for money. It's not very pretty or especially pure; it's not as spectacular as a fully-fueled Falcon blowing up on the launchpad because somebody screwed up the temperature limits of a carbon-fiber-reinforced propellant tank. But it's how big old companies like Boeing do things, and I'm confident they will eventually get it all sorted out.
Meanwhile, Suni and Butch are rationing their clean socks very carefully. Because, you see, it only counts as a successful test flight if they come back in the Starliner that carried them up -- and the second V. P. in charge of flying rockets for money will be in a heap of trouble if this doesn't work as planned.
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* And, kind of indirectly, Sierra Space's Dream Chaser. But it's not competing to carry people at present.
The helium leak in one thruster was a known issue before launch. Physically inspecting and repairing the leak would have meant taking the rocket back to the hanger, de-stacking the capsule and opening up the service module, as I understand it. Boeing, knowing their space operations work is on the line, and NASA somehow decided the leak was minor enough to proceed with the launch. And then the problem got worse and became several thrusters and something happing requiring them to reboot the thruster system before they could dock with the ISS. I would have thought they would have done all the computer modeling they can by now to understand the situation, but I read somewhere they want to power up the thruster system again before returning to see if the leak rates are stable or have gotten worse. If it is worse, they have to decide if they can get the crew down before the helium supply is gone, or if it is safer to send a rescue craft. Either way, I'm afraid this is the end of Boeing's manned operations for some time if not forever.
ReplyDeleteI had a brother-in-law who started with North American Aircraft (which changed hands several times and would have been part of Boeing now) during Mercury and he was with them through the Shuttle program. He would lament how NASA and it's contractors changed and got more bureaucratic over the decades.
I don't know if it's the end. They subbed out the thrusters and it appears to me that the onus is on Aerojet Rocketdyne to deliver. Helium is tricky stuff and it appears to have outsmarted the design team.
ReplyDeleteIt's stacked pretty high with bureaucratic BS -- but if Boeing and NASA haven't figured out how to navigate that, how have they made it this far?
It's odd. When NASA let the contracts to Boeing and SpaceX for manned flight, I thought Boeing would have the easier route to flight. But they went the traditional bureaucratic, design by committee route while SpaceX went with the move fast and learn as things break. The SpaceX was much more like early NASA progress when took us from first Mercury test flight to the moon in a decade. Clearly at this point, SpaceX went the better path.
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